Clinical and immunological features of retinal vasculitis in systemic diseases

Characteristics, Etiology, and Clinical Outcome of Retinal Vasculitis in Tertiary Hospital in Thailand

OBJECTIVE

To analyze characteristics, etiology, and outcome of retinal vasculitis in Central Thailand.

METHODS

A retrospective cohort study.

RESULTS

Retinal vasculitis was found in 10% of uveitis, 74 from 741 uveitis, noninfectious (64.9%) and infectious group (35.1%). The most common cause was Behcet's disease (48.6%). Behcet's disease was the most common cause of all types of vascular leakage on angiography, including capillary (80.4%), venous (56.3%), and arterial leakage (56%). Final visual acuity was 0.86 ± 0.97 logMAR. Cataract was the most frequent complication (42.5%). Acute clinical course (p = .025) and retinal neovascularization (p = .031) were associated with infectious group. Forty-three percent of vasculitis complicated by ischemia required photocoagulation (33%) and anti-VEGF injection (17%). Furthermore, 17% of vasculitis underwent vitrectomy.

CONCLUSION

One-half of the retinal vasculitis in Central Thailand were Behcet's disease. Acute onset and retinal neovascularization may suggest infectious etiology. Retinal ischemia should be cautious and undergo early interventions to prevent sight-threatening complications.

Successful treatment of idiopathic retinal vasculitis with rituximab in two patients

Purpose

To describe results of treatment of idiopathic retinal vasculitis with intravenous rituximab.

Observations

We present two patients with idiopathic retinal vasculitis who required steroid-sparing therapy and achieved steroid-free remission with intravenous rituximab. Rituximab was used as a first-line steroid-sparing agent after steroids in one patient and as a second-line steroid-sparing agent in the other patient. Both patients achieved steroid-free remission of disease with follow up of at least one year after rituximab initiation.

Conclusions and importance

Rituximab achieved steroid-free remission in two patients with idiopathic retinal vasculitis. It should be considered as a treatment option in these patients.

Response to the Second TNF-α Inhibitor (Adalimumab or Infliximab) after Failing the First One in Refractory Idiopathic Inflammatory Retinal Vascular Leakage

Purpose: To determine the response to the second TNF-α inhibitor (adalimumab and infliximab) after failing the first agent in idiopathic inflammatory retinal vascular leakage.Materials and Methods: This was a retrospective observational case series. Patients with the diagnosis of idiopathic inflammatory retinal vascular leakage who had received both infliximab and adalimumab were included in the study.Results: Twelve and 15 patients received adalimumab (Group one) and infliximab (Group two) as the first treatment, respectively. The remission rates between Group one (58.3%) and Group two (66.7%) were not statistically significant. (P = .4) As the second agent, adalimumab was more effective in younger patients (27.5 ± 20.6) compared to older patients (48.75 ± 10.2). (P = .03). Moreover, patients with lower vision responded marginally better to infliximab as the second treatment (P = .06).Conclusion: Either TNF-α inhibitor, adalimumab and infliximab, can be employed in the treatment of the patients with idiopathic inflammatory retinal vascular leakage who fail one of these agents.

Vascular abnormalities in uveitis

Inflammation can involve several ocular structures, including the sclera, retina, and uvea, and cause vascular changes in these tissues. Although retinal vasculitis is the most common finding associated with uveitis involving the posterior segment, other vascular abnormalities may be seen in the retina. These include capillary nonperfusion and ischemia, vascular occlusions, preretinal neovascularization, microaneurysms and macroaneurysms, and telangiectasia. Moreover, vasoproliferative tumors and subsequent coat-like response can develop secondary to uveitis. Fluorescein angiography is ideal for the investigation of retinal vascular leakage and neovascularization, while optical coherence tomography angiography can provide depth resolved images from the superficial and deep capillary plexus and can demonstrate vascular remodeling. Choroidal vascular abnormalities primarily develop in the choriocapillaris or in the choroidal stroma and can appear as flow void in optical coherence tomography angiography and filling defect and vascular leakage in indocyanine green angiography. Extensive choriocapillaris nonperfusion in the presence of choroidal inflammation can increase the risk of choroidal neovascular membrane development. Iris vascular changes may manifest as dilation of vessels in stroma due to inflammation or rubeosis that is usually from ischemia in retinal periphery secondary to chronic inflammation. More severe forms of scleral inflammation, such as necrotizing scleritis, are associated with vascular occlusion in the deep episcleral plexus, which can lead to necrosis of sclera layer and uveal exposure.

RETINAL VASCULITIS, A COMMON MANIFESTATION OF IDIOPATHIC PEDIATRIC UVEITIS?

PURPOSE

Pediatric idiopathic uveitis typically shows anterior segment involvement. Whether retinal vasculitis is an important manifestation of this disease remains unknown and was therefore the subject of this study.

METHODS

This study was performed involving patients with pediatric idiopathic uveitis. Fundus fluorescein angiography was used to assess the presence of retinal vasculitis.

RESULTS

A total of 1,867 patients with pediatric uveitis were seen between December 2008 and January 2018, of whom 1,364 had undergone fundus fluorescein angiography examination. Idiopathic uveitis was the most common entity, accounting for 81.2%. Among these patients with idiopathic uveitis, 79.6% had retinal vasculitis in at least one eye. After 1-year treatment with oral prednisone mostly combined with cyclosporine, 76.3% patients in the retinal vasculitis group achieved control of their ocular inflammation, which was significantly lower as compared with 85.1% in those without (P = 0.008). Retinal vasculitis was an independent predictor for a lower probability of inflammation control after 1-year treatment. Visual function (best-corrected visual acuity > 20/25 in the better seeing eye) was worse in the retinal vasculitis group than in the control group after 5 years.

CONCLUSION

Almost 80% of patients with pediatric idiopathic uveitis show manifestations of retinal vasculitis, which is associated with a lower probability of inflammation control resulting in a worse visual prognosis.

The Anti-Inflammatory Effects of Angiogenin in an Endotoxin Induced Uveitis in Rats

Angiogenin (ANG) is involved in the innate immune system and inflammatory disease. The aim of this study is to evaluate the anti-inflammatory effects of ANG in an endotoxin induced uveitis (EIU) rat model and the pathways involved. EIU rats were treated with balanced salt solution (BSS), a non-functional mutant ANG (mANG), or wild-type ANG (ANG). The integrity of the blood-aqueous barrier was evaluated by the infiltrating cell and protein concentrations in aqueous humor. Histopathology, Western blot, and real-time qRT-PCR of aqueous humor and ocular tissue were performed to analyze inflammatory cytokines and transcription factors. EIU treated with ANG had decreased inflammatory cells and protein concentrations in the anterior chamber. Compared to BSS and mANG, ANG treatment showed reduced expression of IL-1β, IL-8, TNF-α, and Myd88, while the expression of IL-4 and IL-10 was increased. Western blot of ANG treatment showed decreased expression of IL-6, inducible nitric oxide synthase (iNOS), IL-1β, TNF-α, and phosphorylated NF-κB and increased expression of IL-10. In conclusion, ANG seems to reduce effectively immune mediated inflammation in the EIU rat model by reducing the expression of proinflammatory cytokines, while increasing the expression of anti-inflammatory cytokines through pathways related to NF-κB. Therefore, ANG shows potential for effectively suppressing immune-inflammatory responses in vivo.

Ultra-Wide Field Imaging Characteristics of Primary Retinal Vasculitis: Risk Factors for Retinal Neovascularization

Aim: To evaluate patterns of retinal vasculitis with ultra-wide field imaging (UWF) and ascertain the risk factors for retinal neovascularization. Methods: Consecutive patients of retinal vasculitis were included prospectively. Patients with retinal vasculitis secondary to uveitis were excluded. UWF was done for all the patients. Retinal involvement was classified into three zones and area of capillary non-perfusion was stratified into clock hours. Results: Two hundred patients were included, 85% (n = 170) were male. Mean age was 28.99 ± 10.56 years. Clinical examination revealed 65% cases (n = 130) to be bilateral, while UWF angiography detected 72.5% (n = 145) to have bilateral involvement. Retinal neovascularization was present in 47% (n = 188).Presence of posterior disease had very high odds ratio for development of retinal neovascularization as compared to cases restricted to retinal periphery (OR = 45.03, CI = 6.10-332.30, p = < 0.001). Conclusion: UWF imaging is useful in detecting retinal vasculitis, which is otherwise obscure to clinical examination and assessing risk factors for retinal neovascularization.

Clinical Outcome of Retinal Vasculitis and Predictors for Prognosis of Ischemic Retinal Vasculitis

PURPOSE

To determine factors affecting the visual outcome in eyes with retinal vasculitis and the rate of neovascularization relapse in ischemic vasculitis.

DESIGN

Retrospective cohort study.

METHODS

We reviewed 1169 uveitis patients from Moorfields Eye Hospital, London, UK. Retinal vasculitis was observed in 236 eyes (121 ischemic, 115 nonischemic) that were compared with a control group (1022 eyes) with no retinal vasculitis. Ultra-widefield fluorescein angiography images were obtained in 63 eyes with ischemic vasculitis to quantify area of nonperfusion measured as ischemic index.

RESULTS

The risk of vision loss was significantly more in the retinal vasculitis compared with the non-vasculitis group (hazard ratio [HR] 1.67, 95% confidence interval [CI] 1.24-2.25, P = .001). Retinal vasculitis had twice the risk of macular edema compared to the non-vasculitis group. Macular ischemia increased the risk of vision loss in vasculitis eyes by 4.4 times. The use of systemic prednisolone in eyes with vasculitis was associated with a reduced risk of vision loss (HR 0.36, 95% CI 0.15-0.82, P = .01). Laser photocoagulation was administered in 75 eyes (62.0%), out of which 29 (38.1%) had new vessel relapse and required additional laser treatment. The median ischemic index was 25.8% (interquartile range 10.2%-46%). Ischemia involving ≥2 quadrants was associated with increased risk of new vessel formation (HR 2.7, 95% CI 1.3-5.5, P = .003).

CONCLUSIONS

Retinal vasculitis is associated with an increased risk of vision loss, mainly secondary to macular ischemia, and has a higher risk of macular edema compared to eyes with no vasculitis. Ischemia involving ≥2 quadrants is a risk factor for new vessel formation.

Ischemic retinal vasculitis and its management

Ischemic retinal vasculitis is an inflammation of retinal blood vessels associated with vascular occlusion and subsequent retinal hypoperfusion. It can cause visual loss secondary to macular ischemia, macular edema, and neovascularization leading to vitreous hemorrhage, fibrovascular proliferation, and tractional retinal detachment. Ischemic retinal vasculitis can be idiopathic or secondary to systemic disease such as in Behçet's disease, sarcoidosis, tuberculosis, multiple sclerosis, and systemic lupus erythematosus. Corticosteroids with or without immunosuppressive medication are the mainstay treatment in retinal vasculitis together with laser photocoagulation of retinal ischemic areas. Intravitreal injections of bevacizumab are used to treat neovascularization secondary to systemic lupus erythematosus but should be timed with retinal laser photocoagulation to prevent further progression of retinal ischemia. Antitumor necrosis factor agents have shown promising results in controlling refractory retinal vasculitis excluding multiple sclerosis. Interferon has been useful to control inflammation and induce neovascular regression in retinal vasculitis secondary to Behçet's disease and multiple sclerosis. The long term effect of these management strategies in preventing the progression of retinal ischemia and preserving vision is not well understood and needs to be further studied.

Regional morphology and pathophysiology of retinal vascular disease

Disturbances in the retinal vascular supply are involved in the pathophysiology of the most frequent diseases causing visual impairment and blindness in the Western World. These diseases are diagnosed by noting how morphological lesions in the retina vary in shape, size, location and dynamics, and subsequently concluding the presence of a specific disease entity. This diagnostic approach can be used to identify the site of a retinal vascular occlusion, to assess whether retinal diseases are primarily due to changes in the larger retinal vessels or the microcirculation, and to differentiate the relative involvement of the choroidal and the retinal vascular systems. However, a number of morphological manifestations of retinal vascular disease cannot presently be related to the underlying pathophysiology. The review concludes that there is a need for developing new methods for assessing vascular structure and function in the ciliary vascular system supplying the choroid and the optic nerve head. Presently, the study of these structures relies on imaging techniques with limited penetration and resolution into the tissue. Secondly, there is a need for studying oscillations in retinal vascular function occurring within days to weeks, and for studying regional manifestations of retinal vascular disease. This may constitute the basis for future research in retinal vascular pathophysiology and for the development of new treatment modalities to reduce blindness secondary to retinal vascular disease.

Emerging role of antioxidants in the protection of uveitis complications

Current understanding of the role of oxidative stress in ocular inflammatory diseases indicates that antioxidant therapy may be important to optimize the treatment. Recently investigated antioxidant therapies for ocular inflammatory diseases include various vitamins, plant products and reactive oxygen species scavengers. Oxidative stress plays a causative role in both non-infectious and infectious uveitis complications, and novel strategies to diminish tissue damage and dysfunction with antioxidant therapy may ameliorate visual complications. Preclinical studies with experimental animals and cultured cells demonstrate significant anti-inflammatory effects of a number of promising antioxidant agents. Many of these antioxidants are under clinical trial for various inflammatory diseases other than uveitis such as cardiovascular, rheumatoid arthritis and cancer. Well planned interventional clinical studies in the field of ocular inflammation will be necessary to sufficiently investigate the potential medical benefits of antioxidant therapies for uveitis. This review summarizes the recent investigations of novel antioxidant agents for ocular inflammation, with selected studies focused on uveitis.